Am.  Jour.  Pharm. ) 
Oct.,  1882.  I 
Soft  Soap. 
489 
Aluminium  acetate  is  acted  upon  by  chromic  acetate  in  the  same 
manner  as  ferric  acetate,  excepting  that  the  aluminium  is  not  pre- 
cipitated, like  iron,  by  boiling  with  green  chromic  acetate.  The 
behavior  of  the  mixed  solutions  of  aluminic  and  chromic  acetates 
towards  sodium  acetate,  ammonia,  and  caustic  alkalis,  is  exactly 
similar  to  that  which  is  observed  in  mixtures  of  chromic  and  ferric 
acetates. — Jowr.  Chem.  Sog.,  Aug.  1882;  from  Monatsh.  Chem. 
PKEPAKATION  OF  SOFT  SOAP. 
According  to  Ringel  Seifenfabrikant,"  1881,  82),  pure  soft  soap 
consists  mainly  of  potassium  oleate,  potassium  carbonate,  and  the  salts 
contained  in  the  potash  used  for  its  preparation.  Pure  potassium 
oleate  obtained  from  soft  soap  by  treatment  with  potassium  chloride 
is  a  firm,  tough,  slightly  translucent  mass.  Soft  soap  does  not  acquire 
its  translucent  appearance  and  ductile  character  until  after  the  addition 
of  a  solution  of  caustic  and  carbonated  alkali.  Instead  of  finishing 
soaps  with  potash,  potassium  chloride,  sulphate,  borate,  silicate,  etc., 
may  be  used;  sodium  salts,  however,  produce  soaps  of  less  perfection. 
These  salts  have  the  property  of  causing  the  soap  to  combine  with 
water;  100  parts  of  water  require  12  to  15  parts  of  these  salts  to  effect 
this  combination,  so  that  no  watery  particles  separate  on  cooling. 
For  the  preparation  of  green  soft  soap  Starke  ("  Seifenfabrikant," 
1881,  83)  uses  hempseed  oil,  linseed  oil,  and  olei'n.  The  fat  is  intro- 
duced into  the  copper,  mixed  with  an  equal  weight  of  ley  of  18°  to 
20°.B.  (f  potash-ley  and  J  soda),  agitated  repeatedly,  allowed  to  settle 
until  the  next  day,  and  then  heated  to  boiling.  Combination  soon 
takes  place,  and  may  be  recognized  by  the  absence  of  oil,  which  at  the 
commencement  floated  on  the  surface  of  the  ley,  and  by  the  fact  that 
a  sample  placed  on  the  tongue  no  longer  tastes  of  alkali,  but  has  a 
sweetish  taste  resembling  oil.  The  mixture  is  now  subjected  to  gentle 
boiling,  and  treated  gradually  with  ley  of  20  to  24°B.  until  a  trans- 
parent emulsion  is  produced.  At  this  period  the  fire  is  increased  and 
the  boiling  continued  until  the  soap  shows  large  lamellae  on  the  sides 
of  the  copper,  and  only  very  little  froth  is  produced.  The  soap  when 
finished  should  remain  clear  an  cooling. 
According  to  Eichbaum  ("  Seifenfabrikant,^'  1881,  85),  one  of  the 
best  soft  soaps  is  the  so-called  "  natural  grain-soap,^'  which  is  made 
from  potash  ley  (containing  not  more  than  5  per  cent,  of  soda)  and 
